local http = require "http"
local nmap = require "nmap"
local shortport = require "shortport"
local string = require "string"

description = [[
Detects the version of an Oracle Virtual Server Agent by fingerprinting
responses to an HTTP GET request and an XML-RPC method call.

Version 2.2 of Virtual Server Agent returns a distinctive string in response to an
HTTP GET request. However versions 3.0 and 3.0.1 return a generic response that
looks like any other BaseHTTP/SimpleXMLRPCServer. Versions 2.2 and 3.0 return a
distinctive error message in response to a <code>system.listMethods</code>
XML-RPC call, which however does not distinguish the two versions. Version 3.0.1
returns a response to <code>system.listMethods</code> that is different from
that of both version 2.2 and 3.0. Therefore we use this strategy: (1.) Send a
GET request. If the version 2.2 string is returned, return "2.2". (2.) Send a
<code>system.listMethods</code> method call. If an error is
returned, return "3.0" or "3.0.1", depending on the specific format of the
error.
]]

categories = {"version"}

---
-- @output
-- PORT     STATE SERVICE       REASON  VERSION
-- 8899/tcp open  ssl/ovs-agent syn-ack Oracle Virtual Server Agent 3.0 (BaseHTTP 0.3; Python SimpleXMLRPCServer; Python 2.5.2)

author = "David Fifield"
license = "Same as Nmap--See https://nmap.org/book/man-legal.html"


portrule = shortport.version_port_or_service({8899})

local function set_port_version(host, port, version, server)
  port.version.name = "ovs-agent"
  port.version.product = "Oracle Virtual Server Agent"
  port.version.version = version
  if server then
    local basehttp, python = string.match(server, "^BaseHTTP/([%d.]+) Python/([%d.]+)")
    if basehttp and python then
      port.version.extrainfo = string.format("BaseHTTP %s; Python SimpleXMLRPCServer; Python %s", basehttp, python)
    end
  end
  nmap.set_port_version(host, port)
end

function action(host, port)
  local response
  local version = {}

  response = http.get(host, port, "/")
  if response.status == 200 and string.match(response.body,
    "<title>Python: OVSAgentServer Document</title>") then
    set_port_version(host, port, "2.2", response.header["server"])
    return
  end

  -- So much for version 2.2. If the response to GET was 501, then we may
  -- have a version 3.0 or 3.0.1.
  if not (response.status == 501) then
    return
  end

  response = http.post(host, port, "/",
    {header = {["Content-Type"] = "text/xml"}}, nil,
    "<methodCall><methodName>system.listMethods</methodName><params></params></methodCall>")
  if response.status == 403 and string.match(response.body,
    "Message: Unauthorized HTTP Access Attempt from %('[%d.]+', %d+%)!%.") then
    set_port_version(host, port, "3.0", response.header["server"])
    return
  elseif response.status == 403 and string.match(response.body,
    "Message: Unauthorized access attempt from %('[%d.]+', %d+%)!%.") then
    set_port_version(host, port, "3.0.1", response.header["server"])
    return
  end
end
